On 8/7/2019 10:13 AM, Mike Smith VE9AA wrote:
Your #1 friend will be 127' of vertical(ish) wire (ie: inverted L) and a few
ground radial wires or better still 3-4 raised radials and a tall palm tree,
The inverted L seems appealing because:
1. You can tune it to resonance by adjusting the wire length
(no loading coil needed).
2. It typically is a good match to 50 ohms so no matching
network needed.
3. The high drive impedance ~50 ohm makes it seem like there won't
be much ground loss.
It is easy to build and will work ... to some extent.
Unfortunately, the reality is that the increased drive resistance
represents useless horizontally polarized signal power. So the
efficiency in terms of vertical polarized radiated power isn't
all that great.
You will get out better with a T top loaded vertical or a vertical
with "umbrella" wires. You will have to bring along a tapped base
coil to do tuning/matching.
Rick N6RK
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